A maintenance function of a beautiful skin state is one of the fundamental functions of an external preparation for skin such as cosmetics. In order to maintain this beautiful skin state, it is essential to condition the sulci cutis and cristae of the skin by preventing or improving a skin roughness.
In order to attain this object, various humectants such as glycerin, sorbitol, propylene glycol, polysaccharide, and the like have been compounded into cosmetics.
However, among these humectants, e.g., polysaccharide may cause precipitation in the formulation which contains a large amounts of alcohol. Cosmetics which are compounded with glycerin, sorbitol, propylene glycol, and the like in large amounts for the purpose of improving the moisturizing effect, have a tendency to be attended with the sticky feel of use.
In order to remove the sticky feel of use of the cosmetics which is attendant to the improvement of the moisturizing effect, an experiment of compounding trimethylglycine (quaternary ammonium salt) into a cosmetic has been done (cf. Japanese Unexamined Patent Publication Hei No. 6-293625).
A cosmetic which is compounded with trimethylglycine independently can reduce the sticky feel of use. However, in the case where trimethylglycine is compounded in the dosage which is enough to exhibit the improvement effect of the skin state that trimethylglycine is possessed, such an external preparation for skin has a tendency to be attended with "powdery feel of use" by the presence of trimethylglycine. Therefore, the external preparation for skin which is compounded trimethylglycine independently, does not sufficiently satisfy the requirements of users.